Barcode
optical machine-readable representation of data
A barcode or bar code is a method of representing data in a visual, machine-readable symbolic form. Initially, barcodes represented data by varying the widths, spacings and sizes of parallel lines. These barcodes, commonly referred to as linear or one-dimensional (1D), can be scanned by optical scanners known as barcode readers. Later, two-dimensional (2D) variants were developed, using rectangles, dots, hexagons and other patterns, called matrix codes or 2D barcodes. Despite being often included as barcodes, these do not use bars as linear barcodes do. These can be read using purpose-built 2D optical scanners.
Both matrix codes and linear barcodes can also be read by a digital camera connected to a computer. After a photograph of the barcode is taken, software is used to analyze the image to deconstruct and decode the code. A mobile device with a built-in camera, such as a smartphone, can function as this type of barcode reader using specialized application software.
The barcode was invented by Norman Joseph Woodland and Bernard Silver and patented in the US in 1952.
The public source identifies “Barcode” as optical machine-readable representation of data. This brief keeps that definition visible, then builds a research path around Barcode, optical and machine-readable.
Why this record matters
A short description can identify a subject without explaining its stakes. For “Barcode”, the useful work is to connect “optical machine-readable representation of data” to the records capable of establishing context and consequence.
Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 14, 2026. The linked authority identifier is Q856. The Library of Congress control number is sh93000312. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1952.
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Three-step research path
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This entry incorporates text from “Barcode” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.